A music playback apparatus typified by an iPOD (registered trademark), SD-Audio, or the like, uses audio compression technology MP3 (MPEG Audio Layer 3) or the like in order to reduce the size of a data file, and a high-frequency region that cannot be strongly sensed by the human ear—for example, audio of 20 kHz or above—or a weak signal close to a frequency with a high output level is compressed in recording. Consequently, with a conventional audio apparatus, a high-frequency audio range lost due to audio signal compression is reconstituted in a pseudo fashion (see Patent Document 1, for example).